Good morning. The general rule is 2 inch piece of bean = 1 tsp.
Hendel, you must remember that some beans are more flavorful or aromatic than others depending from where they were grown. Sooo, you must write down this information as you go along. I hope this post provides you with insight into substitutions. Good luck & have a nice day.
I have to agree, I've never been able to overwhelm anything I've made with "too much vanilla". Just add to your heart's content :). Most recipes that yield the equivalent of one cake-sized object would probably have between a tsp and a couple tablespoons of the extract.
"If it's chicken, chicken a la king. If it's fish, fish a la king. If it's turkey, fish a la king." -Bender